I'm just speculating, but I'm 99% certain Dave and Chester have an open relationship/agreement of some kind. I present my evidence below.🕵🏽
Point 1: Chester asks for an extra hour off of work one day. Dave asks if this is because it's full-body day at the gym and Chester replies, "Something like that." Then they wink-wink, nudge-nudge each other and Eddy's confused on why. I believe Chester did, indeed, have a "full-body day" that afternoon.
Point 2: Dave is very openly affectionate, dare I say flirty to Eddy. It's one thing to simply be a hugger, but it's another thing to press yourself against your new, cute employee when the job didn't even really call for it. 🧐
Point 3: ...Meta reasons lmao. The author's already confirmed Chester and Dave will get routes eventually. Unless a tragic divorce is in the cards, there has to be a logical explanation for them having routes.